Impact of facility type and surgical management on survival outcomes in colon adenocarcinoma stratified by metastatic burden.

Abstract

11129 Background: Survival for colon cancer varies by facility type, yet the impact of granular metastatic burden and surgical intervention on this disparity remains poorly defined. We examined whether academic survival advantages persist after stratifying by disease extent and evaluated how surgical management contributes to these outcomes. Methods: Using the NCDB (2016–2023), we identified 438,590 adults with colon adenocarcinoma. We compared academic vs. community settings, quantifying metastatic burden by involved organ site count at diagnosis (liver, lung, bone, brain, lymph nodes, viscera; 0–6). Overall survival (OS) was the primary endpoint. Multivariable Cox models adjusted for age, Charlson–Deyo score, clinical stage, and site count. Sequential adjustment for primary tumor resection and metastatic-site surgery was performed to assess potential mediation. Results: Of 438,590 patients, 49.2% were treated at academic centers. Academic cohorts presented with more complex disease, including higher metastatic rates (22.4% vs 20.1%; p < 0.001) and frequent liver involvement (16.9% vs 15.1%; p < 0.001). In stage IV cases, metastatic-site surgery occurred more often at academic facilities (19.1% vs 14.0%). While primary resection rates were high in both cohorts, academic centers achieved superior R0 rates (95.0% vs 94.3%). Adjusted for age, comorbidity, and site count, academic care was associated with a survival benefit (HR 0.93; 95% CI 0.92–0.94). Primary tumor resection strongly predicted OS (HR 0.29; 95% CI 0.29–0.30). Adjusting for primary resection strengthened the academic effect (HR 0.91; 95% CI 0.90–0.92), indicating that surgical management partially mediates this advantage. Conversely, metastatic-site surgery was associated with higher mortality (HR 1.32; 95% CI 1.29–1.34) and did not explain the facility-based survival gap. Conclusions: The survival advantage at academic centers persists regardless of initial metastatic burden and is driven more by primary tumor surgical management than by metastatic-site interventions. These data suggest that improving community outcomes requires broader access to academic-level surgical standards and multidisciplinary care. Ensuring specialized surgical evaluation for high-burden patients is critical, regardless of their initial point of entry into the healthcare system.